AMG: The implementation of the Wibble web server follows. It requires a recent version of Tcl 8.6 with NRE, dated 2010-09-15 or newer. You can find some recent Tclkit builds here: [L1 ] [L2 ] [L3 ]. You're welcome to make code changes directly on this page, but please keep discussion to an absolute minimum.
APN Not clear how the code below relates to the repository at [L4 ]
SEH -- The code below dates from when AMG was using this wiki as his VCS. Probably best to rely entirely on the above-referenced repo.
AMG: Yes, that is correct. I don't know why, assume I must have been busy, but I haven't properly updated these Wiki pages to forward to the repository. Thank you APN and SEH.
The wibble code is now managed in a fossil repository: https://chiselapp.com/user/andy/repository/wibble/timeline?y=ci
This repository has 3 branches:
The code below is the leaf of the SEH-performance branch.
SEH -- I take Andy up on his offer to make code changes here and humbly offer a version I've labeled 0.4.1. Details on the Wibble discussion page. Link to Andy's version 0.4 . Link to jcowgar's mirror of 0.4 on github .
SEH -- ver. 0.4.2: pulled out some unnecessary changes in how request and response vars are handled.
ver 0.4.3: more unneeded code ripped out after consultation with AMG.
Unfortunately the code cannot be highlighted because the regular expressions are confusing the highlighter
#!/usr/bin/env tclsh
# Wibble - a pure-Tcl Web server. https://wiki.tcl-lang.org/23626
# Copyright 2012 Andy Goth. mailto/andrew.m.goth/at/gmail/dot/com
# Available under the Tcl/Tk license. https://www.tcl-lang.org/software/tcltk/license.html
package require Tcl 8.6
# Define the wibble namespace.
namespace eval ::wibble {
variable version 0.4.3
variable zonehandlers
# New: Potentially save time by pre-selecting only matching handlers to be
# evaluated for possible response generation.
# Set value to 1 to activate. As is, default behavior is unchanged.
variable prequalify_handlers 0
}
# ============================== zone handlers ================================
# Define the ::wibble::zone namespace.
namespace eval ::wibble::zone {
namespace path ::wibble
}
# Echo request dictionary.
proc ::wibble::zone::vars {state} {
dict set state response status 200
dict set state response header content-type "" text/html
dict set state response content [template {
<html><head><style type="text/css">
body {font-family: monospace}
table {border-collapse: collapse; outline: 1px solid #000; width: 100%}
th {white-space: nowrap; text-align: left; vertical-align: top}
th, td {border: 1px solid #727772}
tr:nth-child(odd) {background-color: #ded}
tr:nth-child(even) {background-color: #eee}
th.title {background-color: #8d958d; text-align: center}
</style></head><body><table>
% dict for {dictname dictval} $state {
<tr><th class="title" colspan="2">[enhtml $dictname]</th></tr>
% if {$dictname in {request response}} {
% set dictval [dumpstate $dictval]
% }
% dict for {key val} $dictval {
<tr><th>[enhtml $key]</th><td>[enhtml $val]</td></tr>
% }
% }
</table></body></html>}]
sendresponse [dict get $state response]
}
# Redirect when a directory is requested without a trailing slash.
proc ::wibble::zone::dirslash {state} {
dict with state request {}; dict with state options {}
if {[file isdirectory $fspath] && [string index $suffix end] ni {/ ""}} {
append path /
if {[info exists rawquery]} {
append path $rawquery
}
redirect $path
}
}
# Rewrite directory requests to search for an indexfile.
proc ::wibble::zone::indexfile {state} {
dict with state request {}; dict with state options {}
if {[file isdirectory $fspath]} {
if {[string index $path end] ne "/"} {
append path /
}
set newstate $state
dict set newstate request path $path$indexfile
nexthandler $newstate $state
}
}
# Generate directory listings.
proc ::wibble::zone::dirlist {state} {
dict with state request {}; dict with state options {}
if {![file isdirectory $fspath]} {
# Pass if the requested object is not a directory or doesn't exist.
} elseif {[file readable $fspath]} {
# If the directory is readable, generate a listing.
dict set state response status 200
dict set state response header content-type "" text/html
dict set state response content [template {
<html><body>
% if {$path ne "/"} {
<li><a href="../">../</a></li>
% }
% foreach elem [lsort [glob -nocomplain -tails -types d -directory $fspath *]] {
<li><a href="[enhex $elem/]">[enhtml $elem/]</a></li>
% }
% foreach elem [lsort [glob -nocomplain -tails -types f -directory $fspath *]] {
<li><a href="[enhex $elem]">[enhtml $elem]</a></li>
% }
</body></html>}]
sendresponse [dict get $state response]
} else {
# But if it isn't readable, generate a 403.
forbidden $state
}
}
# Execute scripts.
proc ::wibble::zone::scriptfile {state} {
dict with state request {}; dict with state options {}
if {[file readable $fspath.script]} {
dict set state response status 200
source $fspath.script
sendresponse [dict get $state response]
}
}
# Execute templates.
proc ::wibble::zone::templatefile {state} {
dict with state request {}; dict with state options {}
if {[file readable $fspath.tmpl]} {
set chan [open $fspath.tmpl]
set body [chan read $chan]
chan close $chan
dict set state response status 200
dict set state response content [template $body]
sendresponse [dict get $state response]
}
}
# Guess the content type from the URI extension.
proc ::wibble::zone::contenttype {state} {
dict with state request {}; dict with state options {}
set extension [string tolower [string range [file extension $path] 1 end]]
foreach {type pattern} $typetable {
if {[regexp -nocase -- $pattern $extension]} {
dict set state response header content-type "" $type
nexthandler $state
}
}
}
# Send static files.
proc ::wibble::zone::staticfile {state} {
dict with state request {}; dict with state options {}
if {![file isdirectory $fspath] && [file exists $fspath]} {
dict set state response status 200
dict set state response contentfile $fspath
sendresponse [dict get $state response]
}
}
# Send a 301 Moved Permanently.
proc ::wibble::zone::redirect {newurl {state ""}} {
dict set state response status 301
dict set state response header location $newurl
sendresponse [dict get $state response]
}
# Send a 403 Forbidden.
proc ::wibble::zone::forbidden {state} {
dict set state response status 403
dict set state response header content-type {"" text/plain charset utf-8}
dict set state response content "forbidden: [dict get $state request uri]\n"
sendresponse [dict get $state response]
}
# Send a 404 Not Found.
proc ::wibble::zone::notfound {state} {
dict set state response status 404
dict set state response header content-type {"" text/plain charset utf-8}
dict set state response content "not found: [dict get $state request uri]\n"
sendresponse [dict get $state response]
}
# ============================ utility procedures =============================
# [dict getnull] is like [dict get] but returns empty string for missing keys.
proc ::tcl::dict::getnull {dictionary args} {
if {[exists $dictionary {*}$args]} {
get $dictionary {*}$args
}
}
namespace ensemble configure dict -map [dict replace\
[namespace ensemble configure dict -map] getnull ::tcl::dict::getnull]
# Expand a template.
proc ::wibble::template {body} {
set script ""
set pos 0
foreach match [regexp -line -all -inline -indices {^%.*$} $body] {
lassign $match from to
set str [string range $body $pos [expr {$from - 1}]]
if {$str ne ""} {
append script "append # \[" [list subst $str] \]\n
}
append script [string range $body [expr {$from + 1}] $to]\n
set pos [expr {$to + 2}]
}
set str [string range $body $pos end]
if {$str ne ""} {
append script "append # \[" [list subst $str] \]
}
uplevel 1 "set # {}; $script; set #"
}
# Flatten a request/response state dictionary into a form that's easier to log.
proc ::wibble::dumpstate {data {prefix ""}} {
if {![llength $data]} {
return [list $prefix ""]
}
set result {}
dict for {key val} $data {
set key [concat $prefix [list $key]]
if {$key in {header accept query "header content-type"}
|| (([lindex $key 0] in {post query}
|| [lrange $key 0 1] in {"header cookie" "header set-cookie"})
&& ([llength $key] < 3
|| ([llength $key] == 3 && [lindex $key 2] ne "")))} {
lappend result {*}[dumpstate $val $key]
} elseif {[string length $val] > 512} {
lappend result $key (len=[string length $val])
} else {
lappend result $key $val
}
}
return $result
}
# New: create and maintain namespace var with current time in secs,
# to save excessive calls to [clock seconds]
proc ::wibble::update_clock_seconds {} {
variable clock_seconds
set clock_seconds [clock seconds]
after 250 ::wibble::update_clock_seconds
}
# ========================= network input procedures ==========================
# Get a line of data from the current coroutine's socket.
proc ::wibble::getline {} {
set info_coroutine [info coroutine]
set socket [namespace tail $info_coroutine]
while {1} {
if {[chan gets $socket line] >= 0} {
return $line
} elseif {[chan eof $socket]} {
return -level [info level]
} elseif {[chan pending input $socket] > 4096} {
error "line length exceeds limit of 4096 bytes"
}
icc get $info_coroutine readable
}
}
# Get a block of data from the current coroutine's socket.
proc ::wibble::getblock {size} {
set info_coroutine [info coroutine]
set socket [namespace tail $info_coroutine]
while {1} {
set chunklet [chan read $socket $size]
set size [expr {$size - [string length $chunklet]}]
append chunk $chunklet
if {[chan eof $socket]} {
return -level [info level]
} elseif {$size == 0} {
return $chunk
}
icc get $info_coroutine readable
}
}
# ==================== conversion and parsing procedures ======================
# Encode for HTML by substituting angle brackets, ampersands, space sequences,
# and line breaks.
proc ::wibble::enhtml {str} {
string map {< < > > & & \r "" \n "<br />\n" " " \ &\#160;} $str
}
# Encode for HTML tag attribute by substituting angle brackets, ampersands,
# space sequences, and single and double quotes.
proc ::wibble::enattr {str} {
string map {< < > > & & \r "" \n "" " " \ &\#160;
' ' \" "} $str
}
# Encode for HTML <pre> by substituting angle brackets and ampersands.
proc ::wibble::enpre {str} {
string map {< < > > & & \r ""} $str
}
# Encode a query string. The caller must prepend the question mark.
proc ::wibble::enquery {args} {
set query {}
set encode {apply {{str} {string map { " " +}\
[enhex $str {[^-^,./'|!$\w ]}]} ::wibble}}
foreach {key val} [concat {*}$args] {
if {[dict exists $val ""]} {
lappend query [{*}$encode $key]=[{*}$encode [dict get $val ""]]
} else {
lappend query [{*}$encode $key]
}
}
join $query &
}
# Decode a query string into a list. The caller must strip the question mark.
proc ::wibble::dequery {str} {
set query {}
foreach elem [split $str &] {
regexp {^([^=]*)(?:(=.*))?$} $elem _ key val
if {$val ne ""} {
set val [list "" [decode \
[string range $val 1 end]]]
}
lappend query [decode $key] $val
}
return $query
}
# Encode by substituting most non-alphanumerics with hexadecimal codes.
proc ::wibble::enhex {str {pattern {[^-^,./'=+|!$\w]}}} {
set pos 0
while {[regexp -indices -start $pos $pattern $str range]} {
binary scan [string range $str {*}$range] H2 char
set str [string replace $str {*}$range %$char]
set pos [expr {[lindex $range 0] + 3}]
}
return $str
}
# Decode hexadecimal encoding.
proc ::wibble::dehex {str} {
subst -novariables -nocommands\
[regsub -all {%([[:xdigit:]]{2})} [string map {\\ \\\\} $str] {\\u00\1}]
}
# New: replace dehex in places to save extra call to [string map]
proc ::wibble::decode {str} {
subst -novariables -nocommands\
[regsub -all {%([[:xdigit:]]{2})} [string map {+ { } \\ \\\\} $str] {\\u00\1}]
}
# Encode an HTTP time/date.
proc ::wibble::entime {time} {
variable clock_seconds
switch [lindex $time 0] {
abstime {set time [lindex $time 1]}
reltime {set time [expr {$clock_seconds + [lindex $time 1]}]}
}
clock format $time -format "%a %d-%b-%Y %T %Z" -timezone :GMT
}
# Decode an HTTP time/date.
proc ::wibble::detime {str} {
list abstime [clock scan $str]
}
# Decode header list encoding.
proc ::wibble::delist {separator str} {
regexp -all -inline [dict get {
semicolon {(?:[^;"=]+=)?(?:[Ww]/)?"(?:[^\\"]|\\.)*"|\((?:[^\\()]|\\.)*\)|[^;]+}
comma {(?:[^,"=]+=)?(?:[Ww]/)?"(?:[^\\"]|\\.)*"|\((?:[^\\()]|\\.)*\)|[^,]+}
semicomma {(?:[^;,"=]+=)?"(?:[^\\"]|\\.)*"|\((?:[^\\()]|\\.)*\)|[^;,]+}
space {"(?:[^\\"]|\\.)*"|\((?:[^\\()]|\\.)*\)|[^"()\\\s]+}
} $separator] $str
}
# Encode HTTP header quoting when appropriate.
proc ::wibble::enquote {str} {
if {$str eq "" || [regexp {[\0-\040\177\(\)<>@,;:\\"/\[\]\?={}]} $str]} {
return \"[regsub -all {[\0-\010\012-\037\177"\\]} $str {\\&}]\"
} else {
return $str
}
}
# Decode HTTP header quoting.
proc ::wibble::dequote {str} {
if {([string index $str 0] eq "\"" && [string index $str end] eq "\"")
|| ([string index $str 0] eq "(" && [string index $str end] eq ")")} {
regsub -all {\\(.)} [string range $str 1 end-1] {\1}
} else {
return $str
}
}
# Encode an HTTP entity tag.
proc ::wibble::entag {tag} {
lassign $tag type val
switch $type {
tag {return \"[regsub -all {[\0-\010\012-\037\177"\\]} $val {\\&}]\"}
weaktag {return W/\"[regsub -all {[\0-\010\012-\037\177"\\]} $val {\\&}]\"}
}
}
# Decode an HTTP entity tag.
proc ::wibble::detag {str} {
if {[string range $str 0 2] in {W/\" w/\"}} {
list weaktag [dequote [string range $str 2 end]]
} else {
list tag [dequote $str]
}
}
# Encode HTTP headers.
proc ::wibble::enheader {header} {
set str ""
set nl ""
dict for {key val} $header {
if {![llength $val]} {continue}
set comma ""
switch $key {
set-cookie {
# Value is a list of cookie definitions.
dict for {key2 val2} $val {
append str "$nl$key: [enhex $key2]=[enhex [dict get $val2 ""]]"
dict for {key3 val3} $val2 {
switch $key3 {
domain - path {
append str \;$key3=[string map {; %3b} $val3]
} port {
append str \;port
if {[llength $val3]} {
append str =\"[join $val3 ,]\"
}
} discard - httponly - secure {
append str \;$key3
} expires {
switch [lindex $val3 0] {
abstime {append str \;expires=[entime $val3 1]}
reltime {append str \;max-age=[lindex $val3 1]}
}
}}
}
set nl \n
}
} cache-control - pragma {
# Value has format "subkey1=subval1,subkey2=subval2,subkey3".
append str "$nl$key: "
dict for {key2 val2} $val {
append str $comma$key2
if {[dict exists $val2 ""]} {
if {$key eq "cache-control"&& $key2 in {private no-cache}} {
append str =\"[join [dict get $val2 ""] ,]\"
} else {
append str =[enquote [dict get $val2 ""]]
}
}
set comma ,
}
} accept-ranges - allow - connection - content-encoding -
content-language - proxy-authenticate - trailer - upgrade - vary - via -
www-authenticate {
# Value has format "elem1,elem2".
append str "$nl$key: "
foreach val2 $val {
append str $comma[enquote $val2]
set comma ,
}
} warning {
# Value has format "elem1.1 elem1.2 elem1.3,elem2.1 elem2.2".
append str "$nl$key: "
foreach val2 $val {
append str $comma
set space ""
foreach val3 $val2 {
append str $space[enquote $val3]
set space " "
}
set comma ,
}
} transfer-encoding {
# Value has format "elem1;subkey1=subval1;subkey2=subval2,elem2".
append str "$nl$key: "
foreach val2 $val {
append str [dict get $val2 ""]
dict for {key3 val3} $val2 {
if {$key3 ne ""} {
append str \;$key3=[enquote $val3]
}
}
}
} content-disposition - content-type {
# Value has format "elem;subkey1=subval1;subkey2=subval2".
append str "$nl$key: [dict get $val ""]"
dict for {key2 val2} $val {
if {$key2 ne ""} {
append str \;$key2=[enquote $val2]
}
}
} server {
# Value is a server agent definition.
append str $nl$key:
foreach val2 $val {
if {[string index $elem 0] eq "("} {
append str " ([regsub -all {[\0-\010\012-\037\177()\\]}\
$val2 {\\&}])"
} else {
append str " [enquote $val2]"
}
}
} date - expires - last-modified {
# Value is an absolute time.
append str "$nl$key: [entime $val]"
} retry-after {
# Value is an absolute or relative time.
switch [lindex $val 0] {
abstime {append str "$nl$key: [entime $val 1]"
reltime {append str "$nl$key: [lindex $val 1]"}
}}
} etag {
# Value is an entity tag.
append str "$nl$key: [entag $val]"
} age - content-length - content-location - content-md5 -
content-range - location {
# Value is a never-quoted string.
append str "$nl$key: $val"
} default {
# Value is a sometimes-quoted string.
append str "$nl$key: [enquote $val]"
}}
set nl \n
}
return $str
}
# Decode HTTP headers.
proc ::wibble::deheader {str} {
set header {}
foreach {_ key raw} [regexp -all -inline -expanded -lineanchor {
^( [^\s:]+ ) \s*:\s*
( (?: "(?:[^\\"]|\\.)*" | \((?:[^\\()]|\\.)*\) | [^\n] | \n[ \t] )* )
} $str] {
set key [string tolower $key]
set raw [string trim $raw]
set val {}
switch $key {
cookie {
# Value is one or more cookie definitions.
set common {}
set cookie ""
foreach elem [delist semicomma $raw] {
regexp {\s*([^\s=]*)(?:\s*=(.*))?} $elem _ key2 val2
set key2 [string tolower $key2]
if {[string index $key2 0] eq "\$"} {
set key2 [string trim [string range $key2 1 end]]
if {$cookie eq ""} {
dict set common $key2 [dequote $val2]
} else {
dict set params $key2 [dequote $val2]
}
} else {
if {$cookie ne ""} {
lappend val $cookie $params
}
set cookie [dehex $key2]
set params $common
dict set params "" [dehex $val2]
}
}
if {$cookie ne ""} {
lappend val $cookie $params
}
} cache-control - pragma {
# Value has format "subkey1=subval1,subkey2=subval2,subkey3".
foreach elem [delist comma $raw] {
regexp {\s*([^\s=]+)(?:\s*(=.*))?} $elem _ key2 val2
if {$val2 ne ""} {
set val2 [dequote [string trim [string range $val2 1 end]]]
if {$key eq "cache-control"&& $key2 in {private no-cache}} {
set val2 [delist comma $val2]
}
set val2 [list "" $val2]
}
lappend val [string tolower $key2] $val2
}
} connection - content-encoding - content-language - none-match -
trailer - upgrade - vary - via {
# Value has format "elem1,elem2".
foreach elem [delist comma $raw] {
lappend val [dequote [string trim $elem]]
}
} if-match - if-none-match {
# Value has format "tag1,tag2".
foreach elem [delist comma $raw] {
lappend val [detag [string trim $elem]]
}
} warning {
# Value has format "elem1.1 elem1.2 elem1.3,elem2.1 elem2.2".
foreach elem [delist comma $raw] {
set val2 {}
foreach elem2 [delist space $elem] {
lappend val2 [dequote $elem2]
}
lappend val $val2
}
} accept - accept-charset - accept-encoding - accept-language -
expect - te - transfer-encoding {
# Value has format "elem1;subkey1=subval1;subkey2=subval2,elem2".
foreach elem [delist comma $raw] {
set params {}
set subs [delist semicolon $elem]
foreach sub [lrange $subs 1 end] {
regexp {\s*([^\s=]+)(?:\s*=\s*(.*?)\s*)?} $sub _ key2 val2
lappend params [string tolower $key2] [dequote $val2]
}
lappend val [string tolower [string trim [lindex $subs 0]]]
lappend val $params
}
} content-disposition - content-type {
# Value has format "elem;subkey1=subval1;subkey2=subval2".
set elems [delist semicolon $raw]
set val [list "" [string tolower [lindex $elems 0]]]
foreach elem [lrange $elems 1 end] {
regexp {\s*([^\s=]+)(?:\s*=\s*(.*?)\s*)?} $elem _ key2 val2
lappend val [string tolower $key2] [dequote $val2]
}
} user-agent {
# Value is a user-agent definition.
foreach elem [delist space $raw] {
if {[string index $elem 0] eq "("} {
lappend val ([dequote $elem])
} else {
lappend val [dequote $elem]
}
}
} date - expires - if-modified-since - if-unmodified-since -
last-modified {
# Value is an absolute time.
set val [detime $raw]
} if-range {
# Value is an absolute time or an entity tag.
if {[string index $raw end] eq "\""} {
set val [detag $raw]
} else {
set val [detime $raw]
}
} default {
# Value has format "elem".
set val [dequote $raw]
}}
dict set header $key $val
}
return $header
}
# =================== inter-coroutine communication system ====================
# The inter-coroutine communication procedures are in the [icc] ensemble.
namespace eval ::wibble::icc {
namespace export configure destroy get catch put
namespace ensemble create
variable feeds
}
# Lapse (remove) a feed that nothing's interested in anymore.
proc ::wibble::icc::lapse {fid} {
variable feeds
# Clean up the feed's data structures.
set lapsescript [dict get $feeds $fid lapsescript]
dict unset feeds $fid
# Run the lapse script, which may be empty string.
uplevel #0 $lapsescript
}
# Adjust an ICC feed's configuration, creating the feed in the process.
# [icc configure $fid accept|reject ?filter? ?...?]
# [icc configure $fid lapse ?timeout_milliseconds? ?lapsescript?]
proc ::wibble::icc::configure {fid operation args} {
variable feeds
# Initialize the feed if it doesn't already exist.
if {![info exists feeds] || ![dict exists $feeds $fid]} {
dict set feeds $fid {acceptable {exception timeout} lapsetime ""
lapsescript "" lapsecancel "" suspended "" pending ""}
}
# Reset the feed's lapse timeout.
after cancel [dict get $feeds $fid lapsecancel]
dict set feeds $fid lapsecancel ""
# Process the requested operation.
switch $operation {
lapse {
# Store arguments into feed structure, defaulting to "".
dict set feeds $fid lapsetime [lindex $args 0]
dict set feeds $fid lapsescript [lindex $args 1]
} accept {
# Append the arguments to the list of accepted filters.
dict set feeds $fid acceptable [lsort -unique [concat\
[dict get $feeds $fid acceptable] $args]]
} reject {
# Remove all filters that match any of the argument patterns.
set index 0
foreach filter [dict get $feeds $fid acceptable] {
foreach pattern $args {
if {[string match $pattern $filter]
&& $filter ni {exception timeout}} {
dict set feeds $fid acceptable [lreplace\
[dict get $feeds $fid acceptable] $index $index]
incr index -1
break
}
}
incr index
}
}}
# Restart the feed's lapse timeout.
if {[dict get $feeds $fid lapsetime] ne ""} {
dict set feeds $fid lapsecancel [after [dict get $feeds $fid lapsetime]\
[list ::wibble::icc::lapse $fid]]
}
}
# Destroy a feed.
proc ::wibble::icc::destroy {fid} {
variable feeds
# Cancel the feed's readability and timeout handlers.
if {[namespace qualifiers $fid] eq "::wibble"
&& [set socket [namespace tail $fid]] eq [chan names $socket]} {
chan event $socket readable ""
}
after cancel [dict get $feeds $fid lapsecancel]
# Wake suspended coroutines monitoring only this feed with no timeout.
dict for {coro filters} [dict get $feeds $fid suspended] {
if {"timeout" ni $filters} {
lappend suspended $coro
}
}
if {[info exists suspended]} {
dict for {fid2 data2} $feeds {
set index 0
foreach coro $suspended {
if {$coro in [dict get $data2 suspended]} {
set suspended [lreplace $suspended $index $index]
incr index -1
}
incr index
}
}
foreach coro $suspended {
$coro
}
}
# Unset the feed's data structure.
dict unset feeds $fid
}
# Get list of events on any of the named feeds matching any of the filters. If
# an exception event is received, execution jumps to the enclosing [icc catch].
proc ::wibble::icc::get {fids filters {timeout ""}} {
variable feeds
# The exception event is always permitted.
lappend filters exception
set code 0
# Reset the feed lapse timeouts, and check for pending events.
set index 0
foreach fid $fids {
# Reset the feed's lapse timeout.
after cancel [dict get $feeds $fid lapsecancel]
dict set feeds $fid lapsecancel ""
# Gather the pending events that match the request filters.
foreach entry [dict get $feeds $fid pending] {
foreach filter $filters {
if {[string match $filter [lindex $entry 0]]} {
if {[lindex $entry 0] eq "exception"} {
set code 7
}
dict set feeds $fid pending [lreplace\
[dict get $feeds $fid pending] $index $index]
lappend result $entry
incr index -1
break
}
}
incr index
}
}
# If no acceptable events were pending, wait for one to occur.
if {![info exists result]} {
# Install wake-up handlers for readability and timeout, as requested.
set coro [info coroutine]
if {[namespace qualifiers $coro] eq "::wibble"
&& "readable" in $filters && $coro in $fids} {
set socket [namespace tail $coro]
chan event $socket readable [list $coro readable]
}
if {$timeout ne ""} {
lappend filters timeout
if {$coro ni $fids} {
lappend fids $coro
}
set timeoutcancel [after $timeout [list $coro timeout]]
}
# Wait for an event. Maintain each feed's list of suspended coroutines.
foreach fid $fids {
dict set feeds $fid suspended $coro $filters
}
set result [list [yield]]
if {[lindex $result 0 0] eq "exception"} {
set code 7
} elseif {![llength [lindex $result 0]]} {
set result {}
}
foreach fid $fids {
if {[dict exists $feeds $fid]} {
dict unset feeds $fid suspended $coro
}
}
# Remove the readability and timeout handlers.
if {$timeout ne "" && [lindex $result 0 0] ne "timeout"} {
after cancel $timeoutcancel
}
if {[info exists socket]} {
chan event $socket readable ""
}
}
# Restart the lapse timeouts for the feeds monitored by this coroutine.
foreach fid $fids {
if {[dict getnull $feeds $fid lapsetime] ne ""} {
after cancel [dict get $feeds $fid lapsecancel]
dict set feeds $fid lapsecancel [after [dict get $feeds $fid\
lapsetime] [list ::wibble::icc::lapse $fid]]
}
}
# Return the event data. If there was an exception event, return code 7.
return -code $code $result
}
# Execute a script and return any exception events received by [icc get] within
# that script. Other events may be returned too, but only if they happened in
# the same batch as an exception event.
proc ::wibble::icc::catch {script} {
tailcall try $script on 7 events {set events} on ok "" {}
}
# Send event data to the named feeds, or all if "*".
proc ::wibble::icc::put {fids event args} {
variable feeds
# Expand "*" to a list of all feeds that exist at the time [put] is called.
if {$fids eq "*"} {
set fids [dict keys $feeds]
}
# Insist on running from the event loop, never from within a coroutine.
if {[info coroutine] ne ""} {
after 0 [concat [list ::wibble::icc::put $fids $event] $args]
return
}
# Send the event to all feeds whose filters accept it.
set argument [concat [list $event] $args]
foreach fid $fids {
if {[dict exists $feeds $fid]} {
foreach filter [dict get $feeds $fid acceptable] {
if {[string match $filter $event]} {
# Send event to a suspended coroutine watching the feed.
set found 0
dict for {coro filters} [dict get $feeds $fid suspended] {
foreach filter $filters {
if {[string match $filter $event]} {
if {[info commands $coro] ne ""} {
$coro $argument
}
set found 1
break
}
}
}
# If no suspended coroutine, enqueue the event.
if {!$found} {
dict set feeds $fid pending [concat\
[dict get $feeds $fid pending] [list $argument]]
}
break
}
}
}
}
}
# =============================== wibble core =================================
# Advance to the next zone handler using the specified state list.
proc ::wibble::nexthandler {args} {
return -code 5 $args
}
# Send a response to the client.
proc ::wibble::sendresponse {response} {
return -code 6 $response
}
# New: force refresh of handlers and try again with new request settings.
proc ::wibble::retryrequest {request} {
return -code 7 $request
}
# Register a zone handler.
# New: in parallel with list, create hierarchical dict of handlers, from which
# only handlers matching request path can be easily extracted.
proc ::wibble::handle {prefix cmd args} {
variable zonehandlers
variable zh_dict
set prefix [file join / $prefix]
set name [namespace eval zone [list namespace which [lindex $cmd 0]]]
if {$name eq ""} {
error "invalid command name \"$cmd\""
}
set command [concat [list $name] [lrange $cmd 1 end]]
lappend zonehandlers $prefix $command $args
set h_count [expr [llength $zonehandlers]/3 - 1]
dict set zh_dict {*}[file split $prefix/handlers\x0/$h_count] [list $prefix $command $args]
# New: return place of newly-added handler in list.
return $h_count
}
# New: change place of handler in zonehandlers list.
proc ::wibble::promote_handler {old new} {
variable zonehandlers
set old [expr $old * 3]
set new [expr $new * 3]
set handler [lrange $zonehandlers $old $old+2]
set zonehandlers [lreplace $zonehandlers $old $old+2]
set zonehandlers [linsert $zonehandlers $new {*}$handler]
build_zone_dict
}
# New: utility to rebuild zonehandlers dict from scratch.
proc ::wibble::build_zone_dict {} {
variable zonehandlers
variable zh_dict
set zh_dict [dict create]
set h_count 0
foreach {prefix command options} $zonehandlers {
dict set zh_dict {*}[file split $prefix/handlers\x0/$h_count] [list $prefix $command $options]
incr h_count
}
}
# New: return only handlers that are valid matches for give path.
proc ::wibble::get_handlers {path} {
variable zonehandlers
variable prequalify_handlers
variable zh_dict
if {!$prequalify_handlers} {
return $zonehandlers
}
set zhandlers [list]
set handler_dict [dict create]
foreach segment [file split $path] {
lappend subpath $segment
if {[dict exists $zh_dict {*}$subpath handlers\x0]} {
set handler_dict [dict merge $handler_dict [dict get $zh_dict {*}$subpath handlers\x0]]
}
}
foreach key [lsort -dict [dict keys $handler_dict]] {
lappend zhandlers {*}[dict get $handler_dict $key]
}
return $zhandlers
}
# Add, modify, or cancel coroutine cleanup scripts.
proc ::wibble::cleanup {key script} {
upvar #1 cleanup cleanup
if {$script ne ""} {
dict set cleanup $key $script
} else {
dict unset cleanup $key
}
}
# Get an HTTP request from a client.
proc ::wibble::getrequest {port chan peerhost peerport} {
variable clock_seconds
# The HTTP header uses CR/LF line breaks.
chan configure $chan -translation crlf
# Receive and parse the first line. Normalize the path.
regexp {^\s*(\S*)\s+(\S*)\s+(\S*)} [getline] _ method uri protocol
regexp {^([^?]*)(\?.*)?$} $uri _ path query
regsub -all {(?:/|^)\.(?=/|$)} [dehex $path] / path
while {[regsub {(?:/[^/]*/+|^[^/]*/+|^)\.\.(?=/|$)} $path "" path]} {}
regsub -all {//+} /$path / path
# Start building the request structure.
set request [dict create socket $chan peerhost $peerhost peerport $peerport\
port $port rawtime $clock_seconds time [clock format $clock_seconds]\
method $method uri $uri path $path protocol $protocol rawheader {}]
# Parse the query string.
if {$query ne ""} {
dict set request rawquery $query
dict set request query [dequery [string range $query 1 end]]
}
# Receive and parse the headers.
while {[set line [getline]] ne ""} {
dict lappend request rawheader $line
}
dict set request header [deheader [join [dict get $request rawheader] \n]]
# Process qvalues in accept* headers.
foreach {header key} {accept type accept-charset charset
accept-encoding encoding accept-language language te transfercoding} {
set preferences {}
if {[dict exists $request header $header]} {
set options {}
dict for {option params} [dict get $request header $header] {
if {![string is double -strict [dict getnull $params q]]} {
lappend options [list $option 1]
} elseif {[dict get $params q] > 0} {
lappend options [list $option [dict get $params q]]
}
}
foreach elem [lsort -index 1 -decreasing -real $options] {
lappend preferences [lindex $elem 0]
}
}
dict set request accept $key $preferences
}
# Get and parse the request body, if there is one.
if {$method eq "POST"} {
# Get the request body.
if {[dict getnull $request header transfer-encoding] eq "chunked"} {
# Receive chunked request body.
set data ""
while {[scan [getline] %x length] == 1 && $length > 0} {
chan configure $chan -translation binary
append data [getblock $length]
chan configure $chan -translation crlf
}
} else {
# Receive non-chunked request body.
chan configure $chan -translation binary
set data [getblock [dict get $request header content-length]]
chan configure $chan -translation crlf
}
dict set request rawpost $data
# Parse the request body for known content-types.
switch [dict getnull $request header content-type ""] {
multipart/form-data {
# Interpret multipart/form-data (required for file uploads).
set data \r\n$data
set sep \r\n--[dict get $request header content-type boundary]
set beg [expr {[string first $sep $data] + 2}]
set end [expr {[string first $sep $data $beg] - 1}]
set post ""
while {$beg < $end} {
set beg [expr {[string first \n $data $beg] + 1}]
set part [string range $data $beg $end]
set split [string first \r\n\r\n $part]
set val [deheader [string map {\r ""}\
[string range $part 0 [expr {$split - 1}]]]]
dict set val "" [string range $part [expr {$split + 4}] end]
lappend post [dict getnull $val content-disposition name] $val
set beg [expr {$end + 3}]
set end [expr {[string first $sep $data $beg] - 1}]
}
dict set request post $post
} text/plain {
# Interpret text/plain POSTs.
set post ""
foreach elem [lrange [split $data \n] 0 end-1] {
regexp {([^\r=]*)(?:(=[^\r]*))?} $elem _ key val
if {$val ne ""} {
set val [list "" [string range $val 1 end]]
}
lappend post $key $val
}
dict set request post $post
} text/xml {
# Interpret text/xml POSTs, used for Web Services.
dict set request post xml "" [dehex $data]
} application/x-www-form-urlencoded - "" {
# Interpret URL-encoded POSTs.
dict set request post [dequery $data]
}}
}
# The request has been received and parsed. Return it to the caller.
return $request
}
# Get a response from the zone handlers.
proc ::wibble::getresponse {request} {
variable prequalify_handlers
# New: optionally get prequalified handlers guaranteed to match request path
# thus eliminating need to check path against every handler every time.
# Feature activated if prequalify_handlers set to 1, otherwise behavior
# unchanged.
set zonehandlers [get_handlers [dict get $request path]]
set system [list [dict create options {} request $request response {}]]
# Process all zone handlers.
foreach {prefix command options} $zonehandlers {
# Run the zone handler on all states with request paths inside the zone.
set i 0
foreach state $system {
set path [dict get $state request path]
# New: use slightly more efficient path matching method, and
# eliminate a nesting level in loop.
if {!$prequalify_handlers && $prefix ne "/" && [string first $prefix/ $path/]} {
incr i
continue
}
set suffix [string range $path [string length $prefix] end]
# Replace the options in the state dict.
dict set state options $options
dict set state options prefix $prefix
dict set state options suffix $suffix
if {[dict exists $options root]} {
dict set state options fspath\
[file normalize [dict get $options root]/$suffix]
}
# Invoke the handler and process its outcome.
try {
{*}$command $state
} on 5 outcome {
# [nexthandler]: Update the system and continue processing.
set system [lreplace $system $i $i {*}$outcome]
unset outcome
} on 6 outcome {
# [sendresponse]: A response has been obtained. Return it.
return $outcome
} on 7 outcome {
# New: If handler radically rewrites request path, optionally
# start getrequest process over again with refreshed set of
# handlers to match against.
# [retryrequest]: New attempt to get response with altered
# request parameters.
return [getresponse $outcome]
}
incr i
}
}
# Return 501 as default response.
dict create status 501 header {content-type {"" text/plain charset utf-8}}\
content "not implemented: [dict get $request uri]\n"
}
# Default send handler: send the response to the client using HTTP.
proc ::wibble::defaultsend {socket request response} {
variable clock_seconds
# Get the content channel and/or size.
set size 0
set dict_get_request_method [dict get $request method]
set dict_get_response_status [dict get $response status]
if {[dict exists $response contentfile]} {
set dict_get_response_contentfile [dict get $response contentfile]
set size [file size $dict_get_response_contentfile]
if {$dict_get_request_method ne "HEAD"} {
set file [open $dict_get_response_contentfile]
cleanup close_content_file [list chan close $file]
}
} elseif {[dict exists $response contentchan]} {
# New: make channel handling case more similar to file handling case.
set file [dict get $response contentchan]
if {[dict exists $response contentsize]} {
set size [dict get $response contentsize]
} else {
set size [chan pending input $file]
}
cleanup close_content_file [list chan close $file]
} elseif {[dict exists $response content]} {
dict set response content [encoding convertto iso8859-1\
[dict get $response content]]
set size [string length [dict get $response content]]
}
# Parse range request header, and add content-range and -length headers.
set begin 0
set end [expr {$size - 1}]
if {[regexp {^bytes=(\d*)-(\d*)$} [dict getnull $request header range]\
_ begin end] && $dict_get_response_status == 200} {
dict set response status 206
if {$begin eq "" || $begin >= $size} {
set begin 0
}
if {$end eq "" || $end >= $size || $end < $begin} {
set end [expr {$size - 1}]
}
dict set response header content-range "bytes $begin-$end/$size"
}
set end_begin_1 [expr {$end - $begin + 1}]
dict set response header content-length $end_begin_1
# Send the response header to the client.
chan puts $socket "HTTP/1.1 $dict_get_response_status"
chan puts $socket [enheader [dict get $response header]]\n
# If requested, send the response content to the client.
if {$dict_get_request_method ne "HEAD"} {
chan configure $socket -translation binary
if {[info exists file]} {
# Asynchronously send response content from a channel.
set coro [info coroutine]
chan configure $file -translation binary
chan seek $file $begin
chan copy $file $socket -size $end_begin_1 \
-command [list ::wibble::icc put $coro copydone]
if {[llength [set data [icc get $coro copydone]]] == 3} {
error [lindex $data 2]
}
} elseif {[dict exists $response content]} {
# Send buffered response content.
chan puts -nonewline $socket [string range\
[dict get $response content] $begin $end]
}
}
# Close the content file or channel.
if {[info exists file]} {
chan close $file
cleanup close_content_file ""
}
# Return 1 to keep going or 0 if the connection needs to close.
expr {![string equal -nocase\
[dict getnull $request header connection] close]}
}
# Main connection processing loop.
proc ::wibble::process {port socket peerhost peerport} {
try {
# Perform initial configuration.
set coro [info coroutine]
cleanup close_client_socket [list chan close $socket]
cleanup unset_feed [list icc destroy $coro]
icc configure $coro accept readable copydone
chan configure $socket -blocking 0
# Main loop.
while {1} {
# Get request from client, then formulate a response to the request.
set request [getrequest $port $socket $peerhost $peerport]
set response [getresponse $request]
# Determine which command should be used to send the response.
if {[dict exists $response sendcommand]} {
set sendcommand [dict get $response sendcommand]
} else {
set sendcommand ::wibble::defaultsend
}
# Invoke the send command, and terminate or continue as requested.
if {[{*}$sendcommand $socket $request $response]} {
catch {chan flush $socket}
unset request response
} else {
chan close $socket
break
}
}
} on error {"" options} {
# Pass errors to the panic handler.
foreach var {request response} {
if {![info exists $var]} {
set $var {}
}
}
panic $options $port $socket $peerhost $peerport $request $response
} finally {
# Always run scheduled cleanup scripts on coroutine termination.
foreach script [lreverse [dict values $cleanup]] {
catch $script
}
}
}
# Listen for incoming connections.
proc ::wibble::listen {port {socketcommand socket}} {
variable clock_seconds
# New: start storing and updating current time in namespace var to save
# having to do multiple redundant calls to [clock seconds]
if {![info exists clock_seconds]} {update_clock_seconds}
{*}$socketcommand -server [list apply {{port socket peerhost peerport} {
coroutine $socket ::wibble::process $port $socket $peerhost $peerport
} ::wibble} $port] $port
}
# ========================= customizable procedures ===========================
# Log a message. Feel free to replace this procedure as needed.
proc ::wibble::log {message} {
chan puts stderr $message
}
# Log errors and report them to the client, if possible. Customize as needed.
proc ::wibble::panic {options port socket peerhost peerport request response} {
variable clock_seconds
variable errorcount
incr errorcount
set message "*** INTERNAL SERVER ERROR (BEGIN #$errorcount) ***"
if {[dict size $request]} {
dict for {key val} [dumpstate $request] {
append message "\n$key: $val"
}
} else {
append message "\nport: $port"
append message "\nsocket: $socket"
append message "\npeerhost: $peerhost"
append message "\npeerport: $peerport"
append message "\nrawtime: $clock_seconds"
append message "\ntime: [clock format $clock_seconds]"
}
append message "\nerrorinfo: [dict get $options -errorinfo]"
append message "\n*** INTERNAL SERVER ERROR (END #$errorcount) ***"
log $message
if {![dict exists $response nonhttp] && $socket ne ""} {
catch {
chan configure $socket -translation crlf
chan puts $socket "HTTP/1.1 500 Internal Server Error"
chan puts $socket "Content-Type: text/plain;charset=utf-8"
chan puts $socket "Content-Length: [string length $message]"
chan puts $socket "Connection: close"
chan puts $socket ""
chan configure $socket -translation lf -encoding utf-8
chan puts $socket $message
}
}
}
package provide wibble $::wibble::version
# =============================== example code ================================
# Demonstrate Wibble if being run directly.
if {$argv0 eq [info script]} {
# Guess the root directory.
set root [file normalize [file dirname [info script]]]
if {[file isdirectory [file join $root docroot]]} {
set root [file join $root docroot]
}
# Define zone handlers.
set ::wibble::zonehandlers {}
::wibble::handle /vars vars
::wibble::handle / dirslash root $root
::wibble::handle / indexfile root $root indexfile index.html
::wibble::handle / contenttype typetable {
application/javascript ^js$ application/json ^json$
application/pdf ^pdf$ audio/mid ^(?:midi?|rmi)$
audio/mp4 ^m4a$ audio/mpeg ^mp3$
audio/ogg ^(?:flac|og[ag]|spx)$ audio/vnd.wave ^wav$
audio/webm ^webm$ image/bmp ^bmp$
image/gif ^gif$ image/jpeg ^(?:jp[eg]|jpeg)$
image/png ^png$ image/svg+xml ^svg$
image/tiff ^tiff?$ text/css ^css$
text/html ^html?$ text/plain ^txt$
text/xml ^xml$ video/mp4 ^(?:mp4|m4[bprv])$
video/mpeg ^(?:m[lp]v|mp[eg]|mpeg|vob)$ video/ogg ^og[vx]$
video/quicktime ^(?:mov|qt)$ video/x-ms-wmv ^wmv$
}
::wibble::handle / staticfile root $root
::wibble::handle / scriptfile root $root
::wibble::handle / templatefile root $root
::wibble::handle / dirlist root $root
::wibble::handle / notfound
# Start a server, enter the event loop, and provide a console if needed.
if {[catch {::wibble::listen 8080}]} {
# If Wibble is already loaded, do nothing.
} elseif {[catch {package present Tk}]} {
# If there's no Tk, provide no interface, and only enter the event loop.
vwait forever
} elseif {![catch {console show}]} {
# Use the built-in Tk console if it's there, but customize it a bit.
wm withdraw .
console eval [list proc ReloadWibble {} [list consoleinterp eval [list\
source [info script]]]]
console eval {
wm title . "Wibble Web Server"
wm protocol . WM_DELETE_WINDOW exit
.menubar.file delete 1
.menubar.file insert 1 command -label "Reload Wibble" -underline 0\
-accelerator Ctrl+R -command ReloadWibble
.menubar.file entryconfigure 2 -accelerator Ctrl+L
bind . <Control-r> ReloadWibble
}
} else {
# Or provide a command entry window and use normal logging.
wm title . "Wibble Web Server"
wm protocol . WM_DELETE_WINDOW exit
pack [text .e -height 2] -fill both -expand 1
bind .e <Return> {
if {!(%s & 4) && [info complete [set command [.e get 0.1 end]]]} {
set nextid [history nextid]
history add $command
if {![catch $command result]} {
::wibble::log "$nextid %% $command<OK>$result"
.e delete 0.1 end
} else {
::wibble::log "$nextid %% $command<ERROR>$result"
}
break
}
}
focus .e
}
}
# vim: set sts=4 sw=4 tw=80 et ft=tcl: